Chemical characterisation and hypolipidaemic effects of two purified Pleurotus eryngii polysaccharides

This study is focused on the isolation and characterisation of two purified polysaccharide fractions (namely PPEP‐1 and PPEP‐2) from Pleurotus eryngii (P. eryngii) and evaluation of their hypolipidaemic effects. The Congo red analysis indicated that PPEP‐2 but not PPEP‐1 possessed a triple‐helix conformation. The atomic force microscope analysis revealed that PPEP‐1 and PPEP‐2 showed different polysaccharide chain conformations. Importantly, the mice treated with PPEP‐1 showed significantly lowered serum levels of total cholesterol (TC), triglyceride (TG) and low‐density lipoprotein cholesterol (LDL‐c) and increased high‐density lipoprotein cholesterol when compared with the hyperlipidaemia mice induced by the high‐fat diet. However, PPEP‐2 revealed less hypolipidaemic effect than PPEP‐1. Additionally, both PPEP‐1 and PPEP‐2 demonstrated remarkable hypolipidaemic effects by decreasing levels of serum TC, TG and LDL‐c in the hyperlipidaemic model induced by P‐407. Taken together, our findings suggest that the P. eryngii polysaccharides, especially PPEP‐1, could be developed as a natural functional food supplement for preventing hyperlipidaemia.     

Characterisation of phenols and antioxidant and hypolipidaemic activities of Lethariella cladonioides

BACKGROUND: This study aimed to investigate the antioxidant and hypolipidaemic activities of an ethanol extract of Lethariella cladonioides (Nyl.) Krog (EE) and to characterise its chemical constituents. RESULTS: Nine phenols were identified as canarione, thamnolic acid, squamatic acid, vermicularin, norstictic acid, baeomycesis acid, lecanoric acid, barbatinic acid and usnic acid from analysis of EE by using high‐performance liquid chromatography with a diode array detector‐mass spectrometry. In antioxidant analysis in vitro, the highest scavenging rate of EEs on the 2,2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) radicals, superoxide anion, hydroxyl radicals and hydrogen peroxide was 81.55 ± 1.95%, 81.84 ± 4.00%, 74.28 ± 3.71% and 74.28 ± 3.71%, respectively. Meanwhile, after administration of EE for 6 weeks in high fat/cholesterol diet mice, the most significant reduction in levels of serum triglyceride, serum total cholesterol, serum low density lipoprotein cholesterol and liver malondialdehyde were 24%, 20%, 15% and 35%, respectively. The most significant increase in levels of serum high density lipoprotein cholesterol and liver superoxide dismutase was 35% and 88%, respectively. CONCLUSION: L. cladonioides possesses strong antioxidant and hypolipidaemic activities. Copyright © 2011 Society of Chemical Industry     

淫羊藿药渣多糖体外抗氧化活性研究

以提取过黄酮的淫羊藿药渣为原材料,热水法提取多糖,测定淫羊藿药渣多糖的总糖含量、糖醛酸含量和蛋白质含量,并对多糖结构进行红外光谱分析。通过体外抗氧化实验研究其对DPPH自由基、超氧阴离子和羟基自由基的清除能力。结果表明,淫羊藿药渣多糖的总糖质量分数为73.39%,糖醛酸质量分数为6.33%,蛋白质质量分数为1.87%,对DPPH自由基、超氧阴离子和羟基自由基的最大清除率分别为79.96%、92.77%和69.12%,其IC50值分别为0.26、0.03、0.76mg/mL。      

蓬莪术多糖体外抗氧化活性研究

以多年生草本药用植物蓬莪术根茎为原材料,热水浸提法提取多糖,测定蓬莪术多糖的总糖含量、糖醛酸含量和蛋白质含量,并对蓬莪术多糖结构进行红外光谱分析。通过体外抗氧化实验研究蓬莪术多糖对自由基的清除能力以及总还原能力。结果表明,蓬莪术多糖的总糖质量分数为56.13%,糖醛酸质量分数为8.65%,蛋白质质量分数为4.53%。体外抗氧化活性研究结果表明对DPPH自由基、羟基自由基和超氧阴离子有明显清除作用和较强的还原能力,其清除自由基的IC50值分别为0.29、0.44、0.36mg/m L。      

中华牛肝菌多糖的性质及抗氧化活性

中华牛肝菌经热水抽提、乙醇分级沉淀制备多糖(BSP80),测定BSP80的平均分子量大小、单糖组成及其抗氧化活性。结果显示,BSP80的主要平均分子量为53.73 ku,并含有少量4 ku的组分;BSP80主要含有半乳糖、葡萄糖和甘露糖,并含有一定量的半乳糖醛酸和葡萄糖醛酸,阿拉伯糖未检出。BSP80具有较好的还原能力和清除羟自由基能力,其中清除羟自由基的IC50为398.21μg/m L。此外,BSP80能够显著降低H2O2诱导的Hep G2细胞内ROS含量,同时提升细胞内SOD酶活性,且呈一定剂量关系。      

茶叶多糖的药理活性研究进展

茶叶多糖是茶叶中具有生物学活性的复合多糖的简称,其降血糖及防治糖尿病功效最为突出。茶叶多糖可通过保护胰岛β细胞、抑制外源碳水化合物的吸收和调控内源因素(糖代谢酶类和胰岛素)等三条路径来实现降血糖及防治糖尿病的表达。本文从茶叶多糖的其他生物学活性,诸如抗氧化、免疫调节、抗肿瘤、抗凝血、抗疲劳、抑菌杀毒、减肥等方面,阐述近年来茶叶多糖的药理活性及作用机理,以期为进一步研究提供依据。     

黄精多糖的功能活性及应用前景

黄精多糖是黄精的主要功能成分, 研究表明具有一定的抗氧化、免疫调节、抗疲劳、抗病毒、调节血糖血脂、抑菌抗炎等活性, 在功能食品、医疗保健方面具有良好的发展应用前景。本文对黄精多糖的功能活性及在疾病预防与辅助治疗方面的应用进行系统综述, 并对其功能食品开发前景进行展望。     

Hypolipidaemic and antioxidant capacities of polysaccharides obtained from Laminaria japonica by different extraction media in diet‐induced mouse model

This study shows the industrial feasibility of using aqueous methods to produce antioxidative and hypolipidaemic polysaccharides from Laminaria japonica (LJP). Comparison was firstly made among the polysaccharides prepared using different extraction media, that is water alone (LJPW) and citric acid (LJPC), sulphuric acid, hydrochloric acid and phosphoric acid. LJPC enabled the highest extract yield (~11% dry weight), bile salt adsorption rate (~59% dry weight), ABTS radical scavenging activity (IC₅₀ value 1.06 mg mL^?1) and ORAC antioxidant activity (341.87 μmol Trolox g^?1). In animal trial using diet‐induced high‐fat mice, oral administration of LJP produced with citric acid (LJPC) at a high dose (200 mg kg^?1 body mass per day) enabled significantly higher serum HDL‐C, lower LDL‐C/HDL‐C and unaltered LDL‐C, whilst a medium dose (100 mg kg^?1 body mass per day) significantly decreased LDL‐C. Administration of LJP produced with water (200 mg kg^?1 body mass per day) significantly lowered serum LDL‐C. Therefore, LJP may provide dose‐dependent pharmacological and therapeutic effects to combat atherosclerosis through their hyperlipidaemic and antioxidant properties.     

辣椒及辣椒食品中可溶性多糖抗氧化活性研究

研究辣椒及辣椒食品中的可溶性多糖及其抗氧化活性,用硫酸-苯酚法测定了辣椒及辣椒食品中可溶性多糖含量,并测定了多糖提取物对羟基自由基(.OH)、超氧阴离子自由基(O2-.)、二苯代苦味肼基自由基(DPPH.)的清除能力。结果表明,干辣椒可溶性多糖含量较高,为2.06g/100g,制成辣椒食品后,可溶性多糖含量有所损失;辣椒及辣椒食品的可溶性多糖提取物对.OH,O2-.和DPPH.均有一定的清除能力,而且各个样品的可溶性多糖含量与自由基清除能力间呈正相关关系。     

香菇多糖提取工艺的优化及其抗氧化活性研究

为了提高香菇多糖的得率和抗氧化活性,本文采用超声波辅助法提取香菇多糖,在单因素实验的基础上,利用响应曲面法对提取工艺进行优化,并对优化条件下提取的香菇多糖进行体外抗氧化活性测定和结构分析。优化后的最佳提取工艺为超声时间50min、超声温度62℃、超声功率640W。此优化条件下香菇多糖的得率为7.34%,氧自由基吸收能力(ORAC值)为821.35μmol Trolox/g,实验测得数据与预测值无显著性差异。测定产物香菇多糖的羟基自由基的清除能力、ABTS自由基清除能力和还原力,结果表明提取后的香菇多糖具有较高的抗氧化活性。进行红外光谱分析发现超声提取多糖具有多糖的特征吸收峰,说明化学结构没有明显改变。      

Extraction optimisation and antioxidant activities in vitro of polysaccharides from Allium macrostemon Bunge

A four‐factor and three‐level Box–Behnken design was used to optimise the extraction parameters for polysaccharides from Allium macrostemon Bunge (AMBP). As a result, the optimal conditions for AMBP extraction were the following: extraction temperature, 87 °C; ratio of water to raw material, 12 mL g^?1; extraction time, 100 min; and extraction times, 3. Then, a graded ethanol precipitation was used to fractionate the water‐extractable polysaccharides, resulting in three polysaccharides fractions of AMBP40, AMBP60 and AMBP80. During in vitro antioxidant assay, AMBP40 exhibited relative stronger scavenging activities on hydroxyl radical and superoxide radical and metal chelating activity than AMBP60 and AMBP80. The differences in antioxidant activities in vitro might be due to their differences in molecular weight and uronic acid content.     

米糠多糖及硫酸酯化米糠多糖的体外免疫应答和抗肿瘤活性研究

以小鼠黑色素瘤细胞(B16)为抗肿瘤模型,通过MTT比色法评价米糠多糖及硫酸酯化米糠多糖对B16增殖抑制能力。以小鼠巨噬细胞Raw264.7细胞系为免疫模型,通过MTT比色法评价Raw264.7增殖能力,中性红吞噬试验评价巨噬细胞活性,Griess方法检测一氧化氮(NO)释放量,以及酶联免疫(ELISA)检测肿瘤坏死因子(TNF-α)分泌量,考察米糠多糖及硫酸酯化米糠多糖的免疫活性。研究发现:米糠粗多糖(RBP)和米糠多糖纯化组分(RBP2a)主要通过增强机体的免疫功能而间接抑制肿瘤细胞。质量浓度为250μg/m L时,RBP和RBP2a样品组的NO释放量分别为对照组的4.67、6.36倍,TNF-α分泌量为对照组的441.1、465.5倍;RBP直接组和间接组的B16抑制率分别为8.16%、45.55%,间接组的B16抑制率比直接组增长458%。硫酸酯化米糠多糖(SRBP-B,SRBP-D,SRBP2a-B)一方面可以直接抑制B16增殖,质量浓度为1 000μg/m L时,对B16抑制率达73.65%、65.53%、78.43%,另一方面也可通过免疫途径提高NO和TNF-α等细胞因子释放,进一步提高抗肿瘤活性。但高浓度SRBP-B,SRBP-D,SRBP2a-B能抑制Raw264.7增殖,在500μg/m L时,Raw264.7存活率仅为83.26%、81.8%、79.78%。     

不同干燥方法对金针菇多糖抗氧化活性的影响

以金针菇为原料,利用传统水提法提取金针菇多糖（polysaccharides from Flammulina velutipes,FVP）,分别对传统热风干燥多糖（FVP-H）、真空干燥多糖（FVP-V）和冷冻干燥多糖（FVP-F）的成分和抗氧化活性进行研究。结果表明,FVP为酸性多糖,不同干燥方法对其单糖种类没有影响,但会改变单糖的构成比例和糖醛酸含量,FVP-H、FVP-V和FVP-F相对分子质量变化不明显,分别为2342309、2375843和2358437 Da。FVP-H、FVP-V和FVP-F具有较强的清除DPPH自由基、羟基自由基、超氧阴离子自由基的能力和还原力,在一定浓度范围内,多糖与抗氧化活性及还原能力之间呈正相关关系,干燥方法对FVP抗氧化活性具有不同的影响,其中FVP-F抗氧化活性最强,其次是FVP-V和FVP-H,冷冻干燥是制备FVP适宜的干燥方法。      

新疆蔷薇红景天总黄酮抗炎作用及急性毒性研究

目的研究新疆蔷薇红景天总黄酮的抗炎作用及其急性毒性。方法昆明种小鼠60只,随机分为模型组、阿司匹林组(0.2 g/kg)、总黄酮低、中、高剂量组(1.0、2.0、4.0 g/kg),建立二甲苯致小鼠耳肿胀急性炎症模型,考察蔷薇红景天总黄酮对二甲苯致小鼠耳肿胀的影响; SD大鼠50只,随机分为模型组、阿司匹林组(0.14 g/kg),总黄酮低、中、高剂量组(0.7、1.4、2.8 g/kg),建立棉球诱发大鼠肉芽肿慢性炎症模型,考察蔷薇红景天总黄酮对大鼠棉球肉芽肿形成的抑制作用;酶联免疫检测试剂盒测定慢性炎症大鼠血清中肿瘤坏死因子(tumor necrosis factor-α, TNF-α)、环氧化酶-2(cyclooxygenase-2, COX-2)、白介素(interleukin-6, IL-6)、丝裂原激活蛋白激酶(mitogen-activated protein kinase, MAPK)4种炎症因子的含量,考察蔷薇红景天总黄酮的抗炎作用;选取20只昆明种小鼠,随机分为实验组(160 g/kg)和空白组(蒸馏水),灌胃连续给药2 w,观察蔷薇红景天总黄酮的急性毒性。结果与模型组比较,蔷薇红景天总黄酮低、中、高剂量组对二甲苯致小鼠耳肿胀均有显著抑制作用(P0.05, P0.01, P0.01),其抑制率分别为25.75%、38.87%和61.13%;蔷薇红景天总黄酮低、中、高剂量组对大鼠棉球肉芽肿的形成均有明显抑制作用(P0.05, P0.01, P0.01),其抑制率分别为42.06%、53.89%、54.15%;蔷薇红景天总黄酮低、中、高各剂量组均能显著降低大鼠血清COX-2(P0.01)和MAPK的含量(P0.05, P0.01, P0.01);其中、高剂量组能显著降低大鼠血清TNF-α和IL-6的含量(P0.05, P0.01)。结论蔷薇红景天总黄酮具有一定抗急、慢性炎症作用,并且安全无毒。     

玫瑰红景天醇提物不同溶剂萃取物的生物活性

以无水乙醇为溶剂,用索氏提取器对玫瑰红景天粉末进行回流提取,回收乙醇后将乙醇提取物分散和溶解在水相中,依次用环己烷、氯仿、乙酸乙酯、正丁醇分别萃取,得到不同溶剂萃取物。用比色法测定不同溶剂萃取物和水相物中总酚和总黄酮含量,DPPH·法、Fenton法、普鲁士蓝法评价其抗氧化活性以及测试最小抑菌浓度(MIC)和最小杀菌浓度(MBC)。结果表明,乙酸乙酯萃取物中总酚和总黄酮含量最高,分别为(469.32±1.15),(338.57±0.92)mg/g萃取物;不同萃取物和水相物对DPPH·、·OH有不同程度的清除作用且有还原能力,其中乙酸乙酯萃取物和正丁醇萃取物有相对较好的抗氧化活性;总酚和总黄酮含量与抗氧化活性呈显著相关性(P<0.05);对选用的9种菌株均有抑制和灭活作用,MBC值在0.28~16.94mg/mL,对金黄色葡萄球菌株灭活作用更为显著,其中氯仿萃取物和乙酸乙酯萃取物的抗菌效果相对较好。玫瑰红景天乙醇提取物的不同溶剂萃取物及水相物均有抗氧化活性和抗菌活性,有潜在的应用价值。     

蔷薇红景天低聚体原花青素的稳定性和抗衰老研究

本文主要考察光、p H、温度和金属离子等对蔷薇红景天低聚体原花青素稳定性的影响以及其对果蝇的抗衰老作用。稳定性研究结果表明,光照、Fe3+、Sn2+、Al3+等条件可降低原花青素稳定性,低p H、低温以及K+、Mg2+、Na+和Cu2+条件下原花青素较稳定。果蝇抗衰老研究结果显示,低（0.04%）、中（0.12%）、高剂量（0.36%）原花青素对果蝇平均寿命和最高寿命均有不同程度的延长作用,其中中剂量（0.12%）能显著延长果蝇寿命,最高寿命和平均寿命分别可达72 d和55 d;中（0.12%）、高剂量（0.36%）组果蝇SOD活性均显著提高（p<0.05）,且中（0.12%）、高（0.36%）剂量MDA含量均显著下降（p<0.05）。研究为蔷薇红景天低聚体原花青素的深入研究和开发利用提供了科学依据。